Summary: Non‐fusion techniques for surgical correction of scoliosis in an immature spine have recently received substantial interest. Using the porcine scoliosis model, this study aims to investigate the impact of an anterior corrective convex spinal tether on radiographic alignment compared to a control group. Application of an anterior based convex staple‐screw‐tether construct in group 2 resulted in significant progressive correction of the coronal deformity (˜ 50%) without significant sagittal plane re‐alignment. Data from this study support the possibility of clinical techniques for non‐fusion scoliosis correction
Introduction: Non‐fusion techniques for surgical correction of scoliosis in an immature spine have recently received substantial interest. Using an established Porcine Scoliosis Model (PSM), this study aims to investigate the impact of an anterior convex spinal tether on radiographic alignment changes with growth (non‐fusion)
Methods: This IACUC approved Study included 10 immature Yorkshire Pigs divided equally into 2 groups; tether release group (TR) and anterior corrective tether group (AC). All animals underwent scoliosis induction surgery (max. coronal Cobb: 17°‐25°) at 12 weeks of age and progressed a mean 4.0°/week. Once >50° was noted, a second surgical intervention was pursued: TR had release of the inducing tether; AC had tether release and placement of a corrective device over the 5 apical vertebrae. Both groups were observed for an additional 16 weeks with bi‐weekly radiographs. Student t‐test was used to investigate radiographic differences between groups
Results: No significant differences existed between TR and AC regarding; induced Cobb angle, days with deforming tether, or coronal and sagittal alignment before the 2nd intervention (all, p>0.05).
Significant differences in Cobb angle between TR and AC animals were noted following the 2nd intervention (resp. 44.4°±2.2° and 35.0°±2.4°; p=0.001) and bi‐weekly beyond 4 weeks (p<0.01). Final Cobb measurements were 45.0°±2.9° for TR and 24.4°±9.0° for AC (p=0.001).
No significant differences existed in sagittal alignment between TR and AC animals immediately following the 2nd intervention (resp. 14.4°±26.2° and 16.2°±10.2°; p=0.88) and at final follow up; 16.2°±20.9° and 21.2°±12.3° respectively (p=0.65)
Conclusion: Using the PSM, this study investigated radiographic differences between control and treatment groups. Application of a non‐fusion anterior based convex staple‐screw‐tether resulted in significant progressive correction of the coronal spinal deformity (˜ 50%) without significant sagittal plane re‐alignment
Significance: Data from this study support the possibility of clinical techniques for non‐fusion scoliosis correction in the immature spine through growth modulation